SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0ca1dd1deefb04a64cb95adae00e179049f6e11ea663aeee33a8d5ae695ac187' 
  AND token = 'RwnkOk45lpRuidr+PW9hzpoW1Se6jnzW286RNrTEfbQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}